ES2597858B1 - SCANNER FOR BARS - Google Patents

Abstract

Scanner for fuel rods (1) having: inspection devices (10, 20, 60) of rods (1); transport devices (30) to move the bar (1) along the scanner; indicating devices (40) to generate a signal indicative of a scan result corresponding to a scanned bar (1 '').

Description

SCANNER FOR BARS

Technical sector of the invention

The present invention is part of the equipment sector for quality control of fresh fuel rods. Background of the invention

Equipment for performing non-destructive inspections or quality controls of nuclear fuel rods are known.

ES 2056952 -translation of EP0356701A2, which claims priority of US 238,659

-

 It shows a system and method for non-destructive inspections of nuclear fuel rods containing gadolinium ("poisoned") and pure uranium ("non-poisoned"). It has a series of duplicate elements, each of them arranged in a corresponding channel: in one of the channels the poisoned bars are inspected and in the other channel the non-poisoned bars are inspected.

US5108692A, divisional of US 238,659 focuses on the system disclosed in US 238,659.

DE4017100A1, ES441130A1, ES2030774T3, JP61187679, JP 4029083, TW200915345, KR 20110072731 disclose passive systems.

ES 2056952, EP0356701A2, US5108692A or US 238,659 indicate that a first solution in the non-destructive determination of the concentration of the enrichment of a non-poisoned fuel rod, includes the "passive scanning" method, in which gamma rays are quantitatively detected of a characteristic energy emitted during the natural radioactive decay of the fissile material such as U-235. Since U-235 has a relatively long half-life, its spontaneous decay regime and the consequent gamma ray emission regime are low. Consequently, the scanning time required for quantitative enrichment analysis was extremely long, even when the bars were scanned by a distributed array of gamma ray detectors, their computations accumulating. Since all bars have to be tested, manufacturing production is drastically reduced because of this passive scanning solution. Description of the invention

The invention relates to a fuel rod scanner as defined in claim 1. The dependent claims define additional features of the scanner. The invention solves the drawbacks that remain without

Accurate measurement of the bar pitch speed (1) is carried out with calculation means designed to measure for that purpose.

The drag points (31) comprise a pressure wheel (31P) configured to press the bar (1) against at least one drag wheel (31A) configured to drag the bar (1) (operated by its own motor unit, or for one shared with the rest of the drive wheels (31A));

The configuration of the drag points (31), where the bar (1) is dragged between the drag wheel (31A) and the pressure wheel (31P), ensures that the bar is moved without sliding. The drive wheel (31A) can be below the bar and the pressure wheel (31P) above the bar to drag the wheel between the two wheels (31A, 31P) without sliding. Two drive wheels (31A) or one drive wheel (31A) and a second adjacent idler wheel can be installed to improve the grip against the pressure wheel (31P) that is positioned between the two, as shown in the figure 5.

The drive wheels (31A) or the pressure wheel (31P) may have marks to visually check if they are rotating correctly.

The transport means (30) of the bar (1) comprise: a nominal speed (for example 60mm / s) configured to meet precision requirements in a scanning result.

The transport means (30) of the bar (1) further comprise a speed selected from: a re-scan speed, slower than the nominal speed; a high speed, faster than the nominal speed, and combinations thereof.

The speed of re-scanning is useful for re-scanning reviewable bars (1R), that is, bars that have not met the requirements in the scanning but whose result advises a rescan before discarding the bar (1). High speed is useful for scanning special bars or for increasing scanner productivity.

The bar dust collection means (50) (1) are configured to collect bar dust (50) generated in the scanner and obtain collected dust (50R). These may comprise a hopper (51) below a drag point (31). There may be a hopper (51) under each drag point (31) to collect the maximum dust generated. Where appropriate, these hoppers (51) may have extensions to capture the dust generated at other points of the scanner.

The dust collection means (50) can also comprise a pneumatic system (52) configured to evacuate the collected dust (50R). In one embodiment,

Claims (8)

1. Scanner for fuel rods (1) comprising: 1a) inspection means (10, 20, 60) of rods (1); 1b) means of transport (30) to move the bar (1) along the scanner; characterized in that it comprises: 1c) indicating means (40) for generating a signal indicative of a scan result corresponding to a scanned bar (1 ’); 1d) auxiliary means selected from: 1d1) fairing means (80); 1d2) air conditioning means (70); 1d3) bar dust collection means (50) (1); 1d4) signal processing means (84); and combinations thereof.

2.

 Scanner for fuel rods (1) according to claim 1 characterized in that the indicative signal is selected between admissible bar (1A), inadmissible bar (1N) and revisable bar (1R).

3.

 Scanner for fuel rods (1) according to claim 1 characterized in that the transport means (30) of the bar (1) comprise three or more drag points (31) of the bar (1) aligned along a parallel longitudinal axis to a longitudinal axis of the bar (1).

Four.

 Scanner for fuel rods (1) according to claim 3 characterized in that the drag points (31) are spaced apart from each other a distance (D) less than a means of a bar length (L) (1).

5.

 Scanner for fuel rods (1) according to claim 4 characterized in that the distance (D) is less than 600mm.

6.

 Scanner for fuel rods (1) according to claim 3 characterized in that the drag points (31) are synchronized to ensure uniformity in the drag of the bar (1).

34. Method of scanning fuel rods (1) comprising: 34a) inspect by inspection means (10, 20, 60) a bar to be inspected (1 ’) to obtain a scan result of a scanned bar (1’); 34b) assign a selected signal between admissible bar (1A), inadmissible bar (1N) and revisable bar (1R) to a scanned bar (1 ’) depending on the scan result. SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201531074 SPAIN Date of submission of the application: 21.07.2015 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: G21C17 / 06 (2006.01) RELEVANT DOCUMENTS

Category

56 Documents cited Claims Affected

X

US 5108692 A (SCHOENIG, F. et al.) 28.04.1992, summary; column 3, line 58 - column 4, line 64; column 5, line 50 - column 6, line 24; column 6, line 29 - column 7, line 65; Figure 1. 1-11, 16-19, 22-34

Y

12-15, 20, 21

TO

WO 2005/101997 A2 (FROMATOME ANP INC.) 03.11.2005, summary; page 6, line 21 - page 7, line 5; page 7, line 21 - page 9, line 4; Figure 1. one

Y

12-15

TO

US 5602885 A (AHMED, H. et al.) 11.02.1997, summary; Figures 3 and 4. 1, 16, 17

Y

twenty

TO

EP 0526752 A1 (WESTINGHOUSE ELECTRIC CORPORATION) 10.02.1993, summary; column 3, lines 33-44; column 4, lines 38-53; Figures 1 and 2. 1, 16, 17

Y

twenty-one

TO

JP S63171395 A (MITSUBISHI GENSHI NENRYO KK) 15.07.1988, 1, 3-6, 16, 17, 19,

Whole document.

22

TO

EP 0280925 A1 (WESTINGHOUSE ELECTRIC CORPORATION) 07.09.1988, 1, 16, 17, 22, 24,

whole document.

25

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims □ for claims no:

Date of realization of the report 19.12.2016

Examiner Ó. González Peñalba Page 1/6

SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201531074 SPAIN Date of submission of the application: 21.07.2015 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: G21C17 / 06 (2006.01) RELEVANT DOCUMENTS

Category

56 Documents cited Claims Affected

To

JP H06194491 A (HITACHI LTD.) 15.07.1994, Entire document. JP 2000292585 A (NIPPON NUCLEAR FUELS KK) 20.10.2000, Entire document. 1, 16, 17, 21 1, 2, 16, 26, 30-34

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims □ for claims no:

Date of realization of the report 19.12.2016

Examiner Ó. González Peñalba Page 2/6

REPORT OF THE STATE OF THE TECHNIQUE Application number: 201531074 Minimum documentation sought (classification system followed by classification symbols) G21C Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, EPODOC, WPI, INSPEC State of the Art Report Page 3/6  WRITTEN OPINION Application number: 201531074 Date of Written Opinion: 19.12.2016  Statement Novelty (Art. 6.1 LP 11/1986) Claims 2-34 YES Claims 1 NO Inventive activity (Art. 8.1 LP11 / 1986) Claims YES Claims 1-34 NO The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986). Opinion Base.- This opinion has been made on the basis of the patent application as published. State of the Art Report Page 4/6  WRITTEN OPINION Application number: 201531074 1. Documents considered.- The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

US 5108692 A (SCHOENIG, F. et al.) 04/28/1992

D02

WO 2005/101997 A2 (FROMATOME ANP INC.) 03.11.2005

D03

US 5602885 A (AHMED, H. et al.) 11.02.1997

D04

EP 0526752 A1 (WESTINGHOUSE CORPORATION) ELECTRIC 10.02.1993

2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement It is considered that the invention defined in the first claim of the present Application is not new because it is identically collected in the state of the art. Indeed, in document D01, cited with category X for this claim (in addition to others) in the Report on the State of the Art (IET) and considered the closest technological background to the object defined therein, a scanner is described for fuel rods ("active scanner" - see, for example, the summary [in the following, the references in brackets refer to this document D01] -) comprising:

•

bar inspection means (for example, the magnetometer or densitometer - column 4, lines 10-16–);

•

indicating means for generating a signal indicative of a result corresponding to a scanned bar ("test data", "background radiation data" ... - column 4, lines 12 and 21 - are generated, which obviously constitute indicative signals of a scan result);

•

auxiliary means, comprising signal processing means (the signals are analyzed by computer and compared with the corresponding applicable specifications - column 5, line 67 - column 6, line 2).

It is concluded, therefore, that D01 identically anticipates the object of said first claim, at least in its alternative aspect 1d4), whereby this claim is novel in accordance with Article 6 of the current Patent Law. On the other hand, it is considered that the remaining claims 2-34 lack inventive activity because they can be evidently deduced from the state of the art by a person skilled in the art. Thus, claims 2-11, 16-19 and 22-34 collect various aspects or details of the scanner for bars that are either already collected or are obviously deductible from the characteristics specified in D01, such as the addition of categorization of "bar reviewable "to those of" admissible "and" inadmissible "(" rejectable "in D01), obvious in cases of uncertain results of the scan and also recorded in other documents of the prior art, the presence of at least two drag points effective per bar at all times (intuitive in Figure 1 of D01 - if not, the bar would fall -), as well as their distances (depending on the known dimensions of the fuel rods) and configuration (drag wheel and wheel pressure, as shown in Figure 1), the various aspects related to the drag speed (in column 6, line 5 of D01 we speak of a "tightly regulated and uniform speed", assimilable to the vel Nominal value of the invention, which will obviously be suitable for an optimal scan and will be accompanied by other options - fast, rescanning ... -), the gamma radiation densitometer and the gadolinium meter consisting of an equivalent operating magnetometer ( measuring differential paramagnetic susceptibility), gamma detectors, the identification block (in D01 an optical reader that reads an identifying serial number from each bar - column 5, lines 52-53–), the distribution baskets (a distributor ( “Sorter” –column 4, line 41–) classifies the bars according to the results of the scan, which necessarily implies means of reception, or, equivalently, “baskets”), as well as the application to fresh fuel rods, in lines of production (column 4, line 62), and the method of operation; or they constitute solutions to secondary problems concurrent with the essential of the invention, also solved in the art, such as the closing or separation means, or the air conditioning subsystem, of evident application in the D01 system for the person skilled in the art, faced with such problems. It can be concluded, therefore, that said claims 2-11, 16-19 and 22-34 also lack inventive activity with respect to D01, according to Art. 8 LP. And, finally, with regard to claims 12-15, 20 and 21, these also solve secondary problems that occur concomitantly with the principal of the invention, for which they have found similar solutions in the state of the art. Thus, for example, document D02, cited in the EIT with category Y, in combination with D01, for claims 12-15, describes solutions that involve the collection of a specific powder (CRUD) resulting in the surface study of bars of conventional zircaloy fuel, and therefore susceptible to using conventional dust handling elements such as those of the invention; in document D03, also cited as Y for claim 20, the problem of the study of surface defects is contemplated by the equivalent alternative of optical scanning; and document D04, also categorized as Y in the EIT for claim 21, discusses the study of the diameter by means of a laser profilometer, this time, equivalently, of the fuel pellets themselves, and not of the bars. State of the Art Report Page 5/6  WRITTEN OPINION Application number: 201531074 Such claims also lack inventive activity with respect to the combination of D01 respectively with documents D02, D03 and D04, according to said Art. 8 LP. Ultimately, in the present invention, it is a juxtaposition of known technical solutions to various concurrent problems in the field of active scanning of nuclear fuel rods, already known and equally resolved in the state of the art, without such a combination of solutions can expect surprising or unexpected effects with respect to those that they would have separately. State of the Art Report Page 6/6